How disable delete options menu in Blender 2.8?
There is an option for this in Blender 2.80.

Open "User Preferences" then go to "Keymap" and search for "Delete" and go down to Object Mode -> Delete (object.delete) click the dropdown arrow and check/uncheck 'Confirm'

You can also get there by "Keymap -> 3D View -> Object Mode -> Object Mode (Global) -> "Delete (object.delete)" and check/uncheck confirm